SNAI2 and head and neck squamous cell carcinoma: Overexpression of miR-204-5p suppresses HNSCC tumor growth, metastasis and stemness through inhibiting epithelial-mesenchymal transition (EMT) and Janus kinase 2 (JAK2)/Signal transducer and activator of transcription 3 (STAT3) signaling by targeting SNAIL homolog 2 (SNAI2), suppressor of zeste 12 (SUZ12), histone deacetylase 1 (HDAC1) and JAK2 both in vitro and in vivo.